Solar Terrestrial Activity Report

Activity chart

Last major update issued on October 11, 2022 at 06:00 UT.

Charts (* = updated daily) Data and archive
  Solar wind (*) Solar and geomagnetic data - last month (*)
  Electron fluence (*) Archived daily reports and monthly data since 2003.01 (October 6, 2022)
Solar cycle Solar cycles 23-25 (October 1, 2022) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (October 1, 2022) Noon SDO sunspot count 1K image / 4K (*)
  Solar cycles 1-24 (July 1, 2020) POES auroral activity level [October 2009 - December 2012]
  Comparison of cycles 21-25 (October 1, 2022) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (October 1, 2022) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (August 21, 2022) Cycle 25 spots (final update December 25, 2019)
  Solar cycles 24-25 transition using 365d smoothing Research: Solar Cycle 25 Started on November 17, 2019 with 365 Days Smoothing

Recent activity

The geomagnetic field was quiet to unsettled on October 10 under the weakening influence of effects from CH1105. Solar wind speed at SOHO ranged between 454 and 636 km/sec. The high latitude magnetometer at Andenes recorded quiet to minor storm levels.

Solar flux density measured at 20h UT on 2.8 GHz was 163.2 - increasing 9.1 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 115.86). The Potsdam WDC planetary A index was 9 (STAR Ap - based on the mean of three hour interval ap indices: 9.1). Three hour interval K indices: 23231212 (planetary), 33232212 (Boulder), 44131354 (Andenes).

The background x-ray flux is at the class C1 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 8 active regions using 2K resolution (SN: 226) and in 8 active regions using 1K resolution (SN: 158) SDO/HMI images.

Region 13112 [N19W53] decayed slowly and quietly. Note that SWPC originally included the spots from AR S7901 in this region. SWPC split this region off from what they now consider to be AR 13112 on October 7 and named the group AR 13120.
Region 13116 [N29W42] decayed slowly and quietly.
Region 13118 [N09E08] was quiet and stable.
Region 13119 [N29W02] decayed slightly and produced a few low level C flares. C1 flares: C1.5 @ 20:54, C1.5 @ 21:38 UT

Spotted regions not observed (or interpreted differently) by SWPC:
S7901 [N23W42] decayed slowly and remains capable of producing M class flares. C1 flares: C1.5 @ 04:48, C1.1 @ 07:08, C1.2 @ 23:43 UT
S7912 [N19W12] was quiet and stable.
S7917 [S17E12] was quiet and stable.
New region S7918 [S27E78] rotated into view with a small spot.

AR 13111 behind the northwest limb produced a C1.2 flare at 10:02 UT

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C7.0 00:27   S7901 GOES16  
M1.0/1F 00:47 N24W26 S7901 GOES16  
C3.8 02:45   13119 GOES16  
C4.9 15:45   13115 GOES16  
M2.4 16:28 N24W34 S7901 GOES16  
C2.2 18:39   S7901 GOES16  
C3.2 19:21   S7901 GOES16  
C2.1 22:09   13111 GOES16  
C3.2 23:21   S7901 GOES16  

Coronal mass ejections (CMEs)

October 8-10: No obviously Earth directed CMEs were observed in available LASCO imagery.

Coronal holes

[Coronal hole history (since October 2002)]
[Compare today's report to the situation one solar rotation ago: 28 days ago 27 days ago 26 days ago]

No obvious coronal holes are currently in potentially geoeffective positions.

Propagation

Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over upper middle and high latitudes is poor to fair. Propagation on long distance northeast-southwest paths is poor.

Forecast

Mostly quiet geomagnetic conditions are expected on October 11-13.

Coronal holes (1) Coronal mass ejection (2) M and X class flares (3)
     

1) Effects from a coronal hole could reach Earth within the next 5 days. When the high speed stream has arrived the color changes to green.
2) Effects from a CME are likely to be observed at Earth within 96 hours.
3) There is a possibility of either M or X class flares within the next 48 hours.

Green: 0-30% probability, Yellow: 30-70% probability, Red: 70-100% probability.

Active solar regions


(Click on image for 2K resolution). 4K resolution. Compare to the previous day's image.
0.5K image

When available the active region map has a coronal hole polarity overlay where red (pink) is negative and blue is positive.

Data for all officially numbered solar regions according to the Solar Region Summary provided by NOAA/SWPC, all other regions are numbered sequentially as they emerge using the STAR spot number. Comments are my own, as is the STAR spot count (spots observed at or inside a few hours before midnight) and data for regions not numbered by SWPC or where SWPC has observed no spots. SWPC active region numbers in the table below and in the active region map above are the historic SWPC/USAF numbers. SWPC data considered to be not sufficiently precise (location, area, classification) are colored red.

Active region SWPC date numbered
STAR detected
Spot count Location at midnight Area Classification SDO / HMI 4K continuum
image with magnetic polarity overlays
Comment
SWPC/
USAF
Magnetic
(SDO)
SWPC STAR Current Previous
2K 1K
13112

(13120)

2022.09.30
2022.09.30
31 7 2 N22W41 0420 EKI AXX

area: 0010

location: N19W53

Keeping the original SWPC number for data integrity

SWPC has split this off as AR 13120

S7901 2022.09.30   51 24 N23W42 0670   FKC beta-gamma-delta

SWPC has this as AR 13112

S7902 2022.09.30       N27W45            
13116 2022.10.01
2022.10.03
17 21 11 N30W39 0210 DAO DSO

location: N29W42

13117 2022.10.02
2022.10.03
      S11W81           location: S10W75
13118 2022.10.05
2022.10.06
7 12 7 N08E07 0040 CAO DRO

area: 0030

location: N09E08

S7912 2022.10.05   8 3 N19W12 0012   BXO  
13119 2022.10.06
2022.10.07
27 38 28 N27W08 0180 DAI EAI area: 0230

location: N29W02

S7915 2022.10.07       N31E13            
13120 2022.10.07 2     N18W53 0010 AXX       see AR 13112
S7916 2022.10.09       N37E38            
S7917 2022.10.09   8 2 S17E12 0015   AXX  
S7918 2022.10.10   1 1 S27E78 0005   AXX    
Total spot count: 84 146 78  
Sunspot number: 134 226 158  (total spot count + 10 * number of spotted regions)
Weighted SN: 109 169 101  (Sum of total spot count + classification weighting for each AR. Classification weighting: X=0, R=3, A/S=5, H/K=10)
Relative sunspot number (Wolf number): 147 124 126  

Monthly solar cycle data

Month Average solar flux International sunspot number
(WDC-SILSO)
Smoothed sunspot number (4) Average ap
(3)
Measured 1 AU
2014.02 170.3
(cycle peak)
166.3 146.1 (SC24 peak) 110.5 10.70
2014.04 143.9 144.8 112.5 116.4 (solar max) 7.88
2017.09 91.3 92.3 43.6 18.2 (-1.3) 18.22
(cycle peak)
2019.11 70.2 68.7 0.5 2.0 (-0.6)
(Solar minimum using 365d smoothing:
November 17, 2019)
4.19
2019.12 70.8 68.6 1.6 1.8 (-0.2)
(ISN 13 months smoothed
solar minimum)
3.22
2021.03 76.0 75.2 17.2 21.7 (+2.7) 10.17
2021.04 75.9 76.4 24.5 24.8 (+3.1) 8.40
2021.05 75.3 77.1 21.2 25.8 (+1.0) 6.50
2021.06 79.4 81.8 25.0 27.6 (+1.8) 5.52
2021.07 81.0 83.6 34.3 31.4 (+3.8) 5.51
2021.08 77.7 79.7 22.0 35.4 (+4.0) 6.19
2021.09 87.0 88.2 51.3 40.2 (+4.8) 6.33
2021.10 88.9 88.3 37.4 45.2 (+5.0) 7.38
2021.11 86.2 84.4 34.8 50.8 (+5.6) 9.83
2021.12 103.0 99.8 67.5 55.9 (+5.1) 6.40
2022.01 103.8 100.5 55.3 60.1 (+4.2) 8.92
2022.02 109.1 106.5 60.9 64.8 (+4.7) 10.46
2022.03 117.0 115.8 78.6 68.9 (+4.1) 10.20
2022.04 130.8 131.7 84.0 (74.2 projected, +5.3) 11.79
2022.05 133.8 136.8 96.5 (80.6 projected, +6.4) 7.48
2022.06 116.1 119.8 70.3 (86.5 projected, +5.9) 8.20
2022.07 125.4 129.5 91.4 (93.7 projected, +7.2) 9.51
2022.08 114.2 117.1 75.4 (100.2 projected, +6.5) 10.92
2022.09 135.1 136.5 96.3 (105.2 projected, +5.0) 12.18
2022.10 156.6 (1)   42.6 (2A) / 132.0 (2B) / 120.0 (2C) (108.3 projected, +3.1) (14.6)
2022.11       (111.2 projected, +2.9)  
2022.12       (115.9 projected, +4.7)  
2023.01       (122.0 projected, +6.1)  
2023.02       (127.0 projected, +5.0)  
2023.03       (130.0 projected, +3.0)  
2023.11       (142.5 projected max SC25)  

1) Running average based on the daily 20:00 UTC observed solar flux value at 2800 MHz and any corrections applied to that measurement.
2A) Current impact on the monthly sunspot number based on the Boulder (NOAA/SWPC) sunspot number (accumulated daily sunspots / month days).
2B) Boulder SN current month average to date.
2C) STAR SDO 1K Wolf number 30 day average.
3) Running average based on the quicklook and definitive Potsdam WDC ap indices. Values in red are based on the definitive international GFZ Potsdam WDC ap indices.
4) Source: SIDC-SILSO.

Solar cycles 24-25

Smoothed SF and sunspot numbers

 

This report has been prepared by Jan Alvestad. It is based on the analysis of data from whatever sources are available at the time the report is prepared. All time references are to Universal Time. Comments and suggestions are always welcome.

SDO images are courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.